Art of testing coins or other tokens for genuineness



F. W. HOBAN Feb. 6, 1934.

ART OF TESTING COINS OR OTHER TOKENS FOR GENUINENESS Filed March 9, 1931 m M y W -M QTTORNEYS Patented Feb. 6, 1934 UNITED STATES PATENT OFFICE ART OF TESTING COINS OR OTHER TOKENS FOR GENUINENESS Application March 9, 1931. Serial No. 521,314

12 Claims.

My invention relates to improvements in means and methods for testing coins, tokens or like devices for genuineness, and for retaining or accepting the genuine pieces and devices and refusing or rejecting the spurious or counterfeit ones.

An object of the invention is to effect the elimination of the spurious devices and the acceptance of the genuine ones primarily by the action thereon of electrical forces serving to direct the devices into their respective channels for elimination or acceptance without resorting to or relying upon the use of moving parts.

Another object of the invention is to eifectively distinguish between spurious and genuine devices 1 which differ in electrical properties, such as resistance, but slightly from each other.

Another object of the invention is to effect the elimination of spurious devices of substantially all known metallic materials or compositions and the acceptance of silver alloy coins or devices by subjecting the same to an alternating, pulsating or fluctuating electromagnetic field or fields.

Another object of the invention is to prevent acceptance of spurious devices by manipulation of the switch for controlling the circuits.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends, my invention consists of the novel features of construction, and in the combination, connection and arrangement of parts, and in the steps constituting my method, hereinafter more fully described and then pointed out in the claims.

In the accompanying drawing:

Figure 1 is a front elevation of one form of device constructed according to and embodying my said invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a section thereof on the line 3-3 of Fig. 1; and

Fig. 4 is a section of the lower portion thereof on the line 4 of Fig. 1.

The present invention is particularly adapted for detecting or accepting silver alloy coins, such as dimes, quarters, half dollars, and dollars and rejecting their corresponding counterfeits of other materials or baser metals. The detection of the devices or their distinguishment is accomplished by causing the devices to drop or pass by gravity through a chute, or chutes subject to the efiects of alternating or fluctuating magnetic fields utilizing either an alternating current or a direct current with an interrupter.

Coins, devices or tokens of metallic compositions moving through an alternating or pulsating electromagnetic field develop therein what is known, or herein termed, as eddy currents which vary in strength substantially in accordance with the electrical properties of the metalas in the case of ordinary conductors. These 00 eddy currents and the electromagnetic field re act on each other to retard or even prevent the passage of the coin or device through the field Devices of low resistance are retarded more than those of equal size having a higher resist- 5 ance. Devices of like composition having equal diameters are retarded directly in proportion to their thicknesses. The retarding efiect also increases with the mass of material or area exposed to the flux or field. And again, other things being equal, coins or devices of large diameter are retarded more than devices of lesser diameter because they are exposed to the field for a longer time in passing through the same.

Devices dropping or moving through the chute 76 possess kinetic energy which is a function of the mass and velocity M V), the mechanical force thus developed tending to overcome, or overcoming, the opposing electrical force due to eddy current effect. It is therefore necessary to 80 control, adjust or coordinate these opposing forces so that the numerous slugs or spurious devices of diversified compositions, weights, and dimensions can be readily detected and eliminated while acceptance of the genuine device or coin is insured.

The subject matter of the invention disclosed herein and not claimed is described and claimed in my copending application Serial No. 517,222, filed February 20th, 1931. My method broadly, claimed in said copending application, consists in subjecting the genuine device or silver alloy coin to the action of a series of alternating or pulsating magnetic fields of different strengths acting successively, the first field being 05 adjusted in intensity to eliminate the slugs of certain compositions, and the second field being adjusted in tensity to eliminate the slugs oi. the other compositions. The elimination is effected in the present invention by adjusting the strength of the first field to prevent passage therethrough of the silver coin and slugs 01' high conductivity, such as copper and aluminum slugs, the field being disposed to cause the highly conductive devices to be deflected laterally in the direction of the second field located below and in offset relation to the first field. The second field is then adjusted in strength to deflect laterally the copper and aluminum slugs and allow I the silver coin to pass therethrough. Slugs paratus, shown adapted for a quarter, as one ex-- ample of its application, comprises a support 10 having a pair of plates or panels 12 and 14 of in sulating material disposed vertically thereon and secured. together in spaced relation with the separators 16 and 16a therebetween. The separator 16 extends vertically along one edge of the panels and the separator 16a extends vertically along the other edge of the panels, both separators terminating short of the lower end of the panels to form lateral discharge outlets 18 and 20 for the devices submitted for test. The

separator 16a at the upper end of the panels extends inwardly at 16b towards separator 16, terminating short thereof to form an opening or entrance 22 aligned with a corresponding opening 24 through the end member 26 of the support 10. The devices presented for test are inserted through opening 24 which is preferably of the size required to receive a coin of the desired denomination and to prevent the insertion of larger coins or devices.

The panels 12 and 14 and separator 16 and 16 as arranged provide a vertical chute portion or passage 28 between the opening 24 and opening 18 and a vertical chute portion or passage 30 extending parallel with the passage 28 in offset relation to opening 24 and leading to the discharge outlet 20.

The passage 28 is subjected to a fluctuating electromagnetic field at point to cause the deflection of certain of the coins or devices pre-' sented for test laterally into the-upper end of the passage 30 and the lower end of the passage 30 is also subjected to a fluctuating electromagneticfield at a point to cause the deflection of certain of the devices laterally for discharge through opening 18. The electromagnetic means 32 and 34 for developing the fields comprise laminated silicon cores 36 and 38 which are substantially closed except for the gaps 40 and 42 receiving the chute portions 28 and 30. The panels 12 and 14 may be perforated to receive the core ends, or may consist of thin insulating material, such as mica as shown. Coils 44 and 46 are disposed about the cores 36 and 38 at opposite sides of the panels. The coils 44 and 46 may be connected to an alternating current source or to a direct current source with an interrupter, the coils of each pair being connected preferably in parallel.

The gap 40 is located in offset relation to the center of the passage portion 28 at the side thereof towards the separator 16. Devices deflected laterally are discharged into passage 30 through an entrance 48 formed between portion 16b and a small separator 50 having an upper edge 52 inclined downwardly towards passage 30 and located slightly below the gap 40, the corner or apex 54 thereof being located substantially in vertical alignment with the vertical edge of portion 16b and in such relation to gap 40 as to cause the device deflected edgewise laterally by the field to be readily forced over the corner 54 into the passage 30.

Separation is efl'ected between the lower portions of the passages 28 and 30 by means of a separator 56. This separator has a vertical edge 58 defining the inner side of the lower portion of the passage 30 terminating in an inclined edge portion 60 extending over the intermediate portion of the core 38 towards the discharge outlet 20. The separator 56 also has edge portion 62 inclined downwardly towards the outlet 18, the edgeportions 58 and 62 forming an apex 64 at the inner side of and near the base of the gap 42 which gap-is also located in oflset relation to 1 the center of passage 30 towards the separator 16a so that certain of the devices are deflected edgewise laterally and forced over the apex 64 for discharge through the common opening 18, the fiux at both gaps being largely applied to the devices at the side thereof remote from the apices 54 and 64.

The intensity or strength of the electromagnetic fields at the gaps 40 and 42 is determined by the amount of iron present in the core portions at the opposite sides of the gaps, the area ofthe core ends and the width of the gaps. The

field at the gap 40 is adjusted so that the num-- ber of lines of force traversing the gap' is sufiicient to prevent the passage of copper and aluminum slugs and silver coins therethrough and to throw or deflect the same edgewise laterally into the passage 30, while allowing the passage of slugs of other compositions therethrough and out through the opening 18. The field at the gap 42 is adjusted to have the lines of force reduced enough to allow the passage of the silver coin therethrough to be discharged through outlet 20 and. sufi'icient to deflect the copper and aluminum slugs edgewise laterally over the apex 64 and out through outlet 18. 'The upper field at 40 is somewhat stronger than the lower field at 42.

The fields at 40 and 42 are saturated at the lowest voltage in the line so that fluctuations-or increasesin line voltage will not cause variation in the field intensity. The core areas at the gaps being equal, the lines of force traversing the gap 42 are preferably reduced by reducing the number of metal laminations in the core ends at the gap 42, the metallic laminations being replaced by laminations of insulating material. In my invention the coin or device is subjected to substantially equal forces at both sides so that there is no tendency for the coin or device to be displaced in a direction at right angles to the plane thereof to cause sticking or jamming j.

sage of the silver coin through the gap, the field then being strong enough to throw out the copper and aluminum. The upper field 40, although preferably saturated, need not be as critically adjusted as the lower field, provided it is strong enough to deflect the silver coin. With this adjustment, slugs such as lead, zinc, tin, brass, etc., readily pass through the gap 40 because they are relatively inert to eddy current effeet.

The coils 44 and 46 are energized by means of after deflection of such spurious devices at the gap 40 but before the devices are deflected by the second gap 42. This means comprises a rocker arm 70 pivoted intermediate its ends to a bracket '72. Spring opposed magnetic armatures 74 are pivotally connected at their outer ends to the lower end of the rocker arm and extend inwardly through the guiding member 76 past the coils 46 towards the core 38 to be attracted thereby when the coils are energized. A stop pin 78 is loosely connected to the other end of the rocker arm and extends through an opening 80 in the separator 16a into the passage 30 and into the path of the device therein. 'When the lower coils 46 are deenergized any device dropping through passage 30 hits the pin 78 and is deflected thereby over the apex 64 to roll down the inclined edge 62 and out through outlet 18. When the lower coils 46 are energized the armatures 74 are drawn inwardly and the pin 78 is retracted or withdrawn from passage 30 to allow free passage of the coin or device.

In operation, the switch 66 is closed and the coin or device is inserted through opening 24. If the device inserted is a slug or a spurious device relatively inert to eddy current effect, such as lead, tin, zinc, and alloys of copper or aluminum, or non-metallic substances, it falls through the first gap 40 without being affected thereby, through passage 28 and out through outlet 18 to be returned. Magnetic slugs such as iron or nickel look at the first gap and are returned through outlet 18 when the circuit is deenergized. If the device inserted is of soft copper or aluminum or a silver coin, the first field deflects the same into the passage 30, the second gap 42 thereupon forcing the device, if spurious, over the apex 64 to be discharged through outlet 18, and allowing any good device or coin to pass therethrough to outlet 20.

Good coins or tokens passing out through the outlet 20 therefor may be received into a suitable container, or diverted for actuating other devices,

such as a bell or other regulating or indicating devices, or mechanism to be controlled by the coins, such as telephone pay boxes, turnstiles, vending machines, money changers, or the like,

with which mechanisms the detecting means embodying the present invention may be incorporated.

In my invention, the elimination or detection of spurious devices is accomplished electrically within a limited space without undue complexity in the number of tests imposed and without requiring the use of moving parts for diverting the coins or devices into their proper channels. The invention is universal in its application and adaptability for refusing or eliminating slugs of all known metals, alloys, and of course non-metallic slugs of glass, fibre or the like.

The principles of the invention, methods, and general arrangement of structure is the same for all silver coins of the United States or foreign countries, for example, coins of the sizes of quarters, dimes, half dollars, and dollars.

In my invention, the devices tested fall by gravity through chutes or channels simple in arrangement, and the entire control of the disposition of the devices is accomplished by adjusting, and controlling the momentum or kinetic energy of the devices and the electromagnetic fields available, and coordinating the same, so that effective distinguishment between the spurious and genuine devices is obtained, particularly between devices which approximate each other in tion, and ample power is available to deflect the electrical properties, such as copper and silver.

The electromagnetic fields as adjusted are immune to voltage fluctuations in the line' so as not to render the device faulty or unreliable in opera-' 80 coins or devices as required without causing sticking or jamming thereof in the chutes or passages.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. The herein described method of distinguishing between genuine and spurious coins, tokens or like devices which consists in subjecting a de-v vice to a fluctuating electromagnetic field made to deflect the genuine device and devices more responsive to eddy current effect than the genuine over one path and to pass the others over another path to be eliminated, and subjecting the device deflected by the first field to a second fluctuating electromagnetic field made to pass the genuine device for acceptance and. to deflect the others into the first path below the first field to be likewise eliminated.

2. The herein described method of distinguishing between genuine and spurious coins, tokens or like devices which consists in causing a device to pass along a path subject to a fluctuating electromagnetic field acting on the device eccentrically and adjusted to deflect a genuine device and devices more responsive to eddy current effect edgewise laterally relative to the path of travel thereof, and to allow other spurious devices to pass therethrough.

3. The herein described method of distinguishing between genuine and spurious coins, tokens or like devices which consists in causing a device to fall by gravity towards a fluctuating electromag-- netic field, and making said field deflect the device if genuine and spurious devices of greater responsiveness to eddy current effect edgewise laterally relative to-the path of travel thereof, and to pass the other devices.

4. The herein described method of distinguishing between genuine and spurious coins, tokens or like devices which consists in causing a device to fall vertically a predetermined distance to a fluctuating electromagnetic field acting on opposite sides of the device to prevent displacement of the device transversely of the plane thereof, and having a strength coordinated with the distance of drop or momentum of the device to pass devices relatively inert to eddy current eifect, and to prevent passage of a genuine device and others of greater responsiveness to eddy current effect therethrough.

5. The herein described method of distinguishing between genuine and spurious coins, tokens or like devices which consists in causing a device to fall towards a fluctuating electromagnetic field acting eccentrically thereon and adjusted to deflect the device if genuine or of greater responsiveness to eddy current effect edgewise laterally to fall through another vertical path in offset relation to the first field, and to pass vertically through said field devices of lesser responsiveness to eddy current effect, and subjecting the device falling through the second path to the action of a fluctuating electromagnetic field acting eccentrically thereon and adjusted to pass a genuine device and deflect a spurious device edgewise laterally towards the first path.

6. An apparatus of the character described comprising fluctuating current electromagnetic means having core portions developing fluctuating magnetic fields, said core portions being arranged in ofiset relation to each other at different elevations, said upper field having a strength sufllcient to deflect devices of relatively high responsiveness to eddy current effect while passing others, and said lower -field 'having a strength suficient to deflect certain of the devices deflected by the first field while passing others, a passage for devices passing directly through the upper field, and a passage for receiving devices deflected by the upper field and conducting the same to the lower field.

7. An apparatus 01' the character described comprising a chute, and a fluctuating current electromagnetic means including a core having separated portions forming a gap receiving said chute, said gap being adjusted to produce a fluctuating magnetic field adapted to deflect the genuine silver device and spurious devices of greater responsiveness to eddy current eflect edgewise laterally relative to the direction of travel thereof and to allow the passage of others.

8. An apparatus of the character described comprising a chute, and a fluctuating current electromagnetic means having core portions forming a gap receiving said chute and traversed by a fluctuating magnetic field, said core portions being disposed in eccentric relation to the device passing through said chute and being adjusted to cause the eddy current efiect to deflect the genuine devices and devices more responsive to eddy current effect edgewise laterally relative to the direction of movement thereof, and an outlet in the chute for the deflected devices.

9. An apparatus of the character described comprising a chute, electromagnetic means having a core portion forming a fluctuating magnetic fleldin operative relation to said chute, said core portion being adjusted to deflect a genuine silver device and devices of greater responsiveness to eddy current effect, and to allow other devices to pass through said field, and being saturated for a relatively low voltage in the line to-render the field immune to line voltage variations.

10'. An apparatus of the character described comprising avertical chute having parallel vertical passage portions, fluctuating current electromagnetic means having separated core portions forming fluctuating electromagnetic gaps, one of said gaps being aligned withthe upper part of'one passage, and the other with the lower part of the other passage, and each being disposed 'n eccentric relation to the devices to be presented thereto; the upper gap being adjusted to deflect edgewise laterally of the direction of travel thereof and into the passage of the lower gap the genuine device and devices having a greater responsiveness to eddy current effect than the genuine, and the lower gap being adjusted to pass the genuine device and to deflect devices of greater responsiveness to eddy current eflect, and certain of said gaps being adjusted to he saturated at relatively low voltage in the line to render the field immune to line voltage variations.

11. An apparatus of the character described comprising a chute having parallel passages therethrough, fluctuating current electromagnetic means including a pair of separated core portions forming gaps at the upper part of one passage and at the lower part of the other, said gaps 7 being arranged eccentrically relative to coins or devices dropping through said passages, the core portions of the upper'gap being adjusted to create a fluctuating magnetic fleld of a strength to deflect the genuine device and devices of greater responsiveness to eddy current eflect than the genuine into the passage to the lower gap and to pass those of lesser responsiveness through the passage or the upper gap to be eliminated, and the core portions of the lower gap being adjusted to create a fleld strength sufllcient to deflect the devices of greater responsiveness to eddy current effect than the genuine and to pass the genuine through the vertical passage of the lower gap, and means for returning the devices deflected by the lower gap into the vertical passage of the upper gap to be eliminated. v

12. An apparatus of the character described comprising electromagnetic means having core portions forming a plurality of fluctuating magnetic fields, the first field being adapted to deflect certain of the devices and pass others and the second field being adapted to deflect certain of the devices deflected by the first fleld and to pass others, a passage between said fields, a switch for controlling the current in said electromagnetic means, and means for preventing passage of devices through the second field should the circuit thereof become deenergized.

, FAIRFIELD W. HOBAN. 

